A dust collector is a cleaning appliance which utilizes a motor to drive vanes to rotate at a high speed to generate an air negative pressure in a sealed housing, so as to suction dust into a dust collecting device and discharge the filtered air out of a fan at an extremely high speed. The dust collectors are classified into dry type dust collectors and wet-dry type dust collectors according their functions. The dry type dust collectors generally include a dust-bag type dust collector and a dust-cup type dust collector.
A conventional dust-cup type dust collector generally includes a two-stage dust-air separation structure. A first-stage structure is used to filter large size dirt in air, and a second-stage structure is used to separate and collect small size debris such as dust particles. In a conventional two-stage dust-air separation structure, a two-stage cyclone is generally generated by the cooperation between a cover plate of a dust cup filter and a cyclone body having multiple cyclone openings, and this structure requires a lot of components, which also requires many and complicated molds and assembly processes. Further, the sealing of each link is difficult to control, and air leakage and dust leakage phenomena are apt to occur, which adversely affects the comprehensive performance of the whole machine.
A conventional two-stage dust-air separation type dust cup structure is arranged axially, in which multiple layers of cone bodies and a cyclone partition plate are axially stacked to achieve an object of separating dust from the gas, thus its filter structure occupies a large proportion of space of the dust cup and occupies too much of the dust-collecting volume of the dust cup, and a dust storage space is limited. Moreover, this two-stage dust-air separation type dust cup structure requires the dust cup to have a relatively high size and a relatively large volume, and is not applicable to a mini dust collector and a portable dust collector, and the application scope thereof is limited.
In view of the above issues, it is necessary to provide a novel two-stage dust-air separation structure to reduce the number of the components, simplify the assembly process, improve the comprehensive performance of the whole machine, and also effectively reduce the space of the dust cup that is occupied by the two-stage dust-air separation structure, to realize the maximum dust storage volume and improve the dust collecting efficiency, thereby allowing the two-stage dust-air separation structure to be applicable to dust collectors of various types and sizes.